BRAF activates and interacts with PAK

Increased p21-activated kinase (PAK) signaling and expression have been identified in aggressive papillary thyroid cancers (PTCs), and thyroid cancer cell motility is PAK1 dependent. McCarty and colleagues used three well-characterized human thyroid cancer cell lines to demonstrate that BRAF knockdown reduced PAK downstream target phosphorylation. In contrast, MEK inhibition did not reduce PAK activity. BRAF knockdown cell migration inhibition was reversed by MEK1 or PAK1 overexpression, demonstrating involvement of both signaling pathways in cell motility. They went on to demonstrate that acute in vivo BRAFV600E induction in murine thyroid glands results in increased PAK expression.

Read the full article at McCarty et al. (2014) Endocrine-Related Cancer 21 865–877. DOI:10.1530/ERC-14-0424